Helicobacter pylori

What is being tested?
These tests detect an infection caused by a bacterium known as Helicobacter pylori. This bacterium is recognised as the main cause of peptic ulcers and is also associated with the development of stomach cancer.

How is the sample collected for testing?
The type of sample depends on what the doctor requests. It may be a stool sample to detect H. pylori antigen or a blood sample to detect antibodies against the bacterium.

A more invasive test requires a procedure called endoscopy, which uses a probe passed into the stomach to take a small piece of tissue (biopsy).
A biopsy can be used to detect other causes of stomach problems as well as to test for H. pylori in the laboratory.
H. pylori produces urease, a particular enzyme that allows it to survive in the acid environment of the stomach.
The laboratory can check for this bacterium by detecting this enzyme in the tissue sample.
The tissue can also be examined under the microscope by a pathologist, who will look for the bacterium or other signs of disease that could explain the symptoms.

Sometimes the breath test can be used instead of a biopsy.
You will need to drink a liquid containing a mildly radioactive substance.
If H. pylori is present in the gut, the substance will be broken down into labelled carbon dioxide.
By testing a sample of your exhaled breath, the laboratory can tell whether this organism is present

How is it used?
When is it requested?
What does the test result mean?
Is there anything else I should know?

How is it used?
A positive H. pylori test indicates that the gastrointestinal pain may be caused by this bacterium. Taking antibiotics will eliminate the bacterium, stopping the pain and the ulceration.

When is it requested?
If you have gastrointestinal pain and symptoms of an ulcer, your doctor may request one of the H. pylori tests to see whether there is evidence of this infection. These tests may also be requested after a course of antibiotics to show that H. pylori has gone. A follow-up test is not requested for every patient.

What does the test result mean?
A positive H. pylori test, whether by antibody, antigen or breath test, means that you have been infected with this organism. Recent scientific evidence shows that this bacterium causes stomach ulcers and that appropriate treatment eliminates the bacterium and stops the disease.

Is there anything else I should know?
Gastrointestinal diseases occur for many reasons; H. pylori is only one of the causes

1. How is peptic ulcer caused by H. pylori treated?
2. Will everyone with H. pylori get an ulcer?
3. How do people become infected with H. pylori?
4. Do people treated for H. pylori benefit?
5. My father has an ulcer and only takes antacids. Why am I taking antibiotics?

1. How is peptic ulcer caused by H. pylori treated?
The doctor usually prescribes a combination of antibiotics and a bismuth treatment for several weeks

2. Will everyone with H. pylori get an ulcer?
No, many people show signs of infection but have no symptoms of an ulcer.

3. How do people become infected with H. pylori?
The bacteria are transmitted by eating or drinking water contaminated with human faeces. Animals do not carry the bacterium in their gut; it is found only in humans. H. pylori infection is one of the most common infections in humans, affecting about 50% of the world’s population. In the USA and other developed countries the infection rate is lower thanks to better hygiene and socio-economic conditions

4. Do people treated for H. pylori benefit?
Most people treated with antibiotics eliminate this bacterium from their gut. However, antibiotic resistance can occur, and the bacterium then continues to multiply despite appropriate treatment

5. My father has an ulcer and only takes antacids. Why do I need antibiotics?
Years ago doctors did not know about H. pylori. Before 1994 peptic ulcers were not recognised as an infectious disease, so the only treatment prescribed for ulcers was a change of diet and antacids to relieve the pain.